Typewriting machine



p 1942- H; LQPITMAN 2,294,691

TYPEWRITING MACHINE Filed March 4, 1940 V/dlElV/l/A In- J7 5 INVENTORHEN/Q! L. P/7/74/V Patented Sept. 1, 1942 TYPEWRITIN G MACHINE Henry L.Pitman, Hartford, Conn., assignor to Underwood Elliott Fisher Company,New York, N. Y., a corporation of Delaware Application March 4, 1940,Serial No. 322,079

Claims.

This invention relates to typing machines and more particularly toconnections whereby an operatable part is connectible to a power drivensnatch roll for a consequent power driven stroke of said part.

Such connection may include a connector, preferably a draw link,connected to the operatable part and movable into position fordetermining its connection with a rotary toothedsnatch-roll.

An object of the invention is to control the speed at which the toothedperiphery of the snatch roll drives the link, and hence the operatablepart, particularly at the start of the power driven motion of said linkand part so that said start may be effected smoothly to reduce jarringand wear upon the mechanism. 7

The draw link may have a toothed pawl or rotary member pivoted theretoas the medium engaged by the snatch roll. A further object is to havesuch pawl or member acted upon by the snatch roll as a lever to move thedraw link at a lesser speed than the linear speed of the snatch rollteeth. Forthis purpose said lever may react against an abutment. Thelever action also serves to urge the pawl into proper engagement withthe snatch roll.

The pawl acts as a lever, in moving the link, during a time that thepawl is being rotated from a normal position on the link to a stopposition on said link.

Another object of the invention is to provide for adjustment to vary theperiod in which the pawl acts as a lever to control the speed ofmovement of the link.

The above and other objects and features of the invention will be fullyunderstood by reference to the accompanying drawing in which:

Figure 1 is a side elevation of a type action, illustrative of anoperatable part, and connections whereby said type action is connectibleto a snatch roll.

Figures 2 and 3 are side elevations and represent relative positions ofthe parts at difierent stages.

||l represents a toothed snatch roll journaled in the frame of themachine and connected to and constantly rotated counterclockwise by asuitable motor, not shown. A type bar H is swingable upwardly andrearwardly from the normal Figure 1 position to strike a platen l2. Abell crank l3 connects said type bar to an operating lever l4 connectedby a link Hi to a lever l6 fulcrumed on a transverse rod H in theframework. Pivoted at l8 to a depending arm of said lever l6 there is alever having a rearwardly extending arm forming a draw link l9 and aforwardly extending arm 20 engageable by the key plunger 2|.

Depression of the key plunger 2| rocks said lever I9, 20counterclockwise about I8 thereby raising the draw link Hi to bring atoothed pawl 22 pivoted on said link H! at 23 into engagement with thesnatch roll l0. As will be noted from the drawing, the pitch of theteeth of the pawl 22 may be slightly less than the pitch of the teeth ofthe snatch roll H).

The pawl has a tail 24 which in the normal Figure 1 position of theparts extends rearwardly and lies flat upon a transverse bar 25 secured,adjustably as will later be described, to the typewriter framework.

Upon raising the draw link by operation of the key plunger 2| and hencemeshing the toothed pawl 22 with the teeth of the snatch roll the latterinitially rotates said pawl clockwise about the pivot 23 relatively tothe link. While the pawl is being so rotated, the tail thereof reacts asa cam against a corner 26 of the abutment bar 25 so that the pawl isurged toward the snatch roll. It may be during this time and possiblyfor a period thereafter that the pawl acts as a lever of the secondorder to move the draw link to the right as viewed in the drawing. Itwill be seen, therefore, that while the pawl is acting thus as a lever,the draw link |9 will be moved to the right at less speed than thelinear or peripheral speed of the snatch roll teeth. The pawl thus actsas a lever during the time it is rotated to the position where itscorner 21 stops against an edge 28 of the draw link l9 as shown inFigure 3.

Further rotation of the snatch roll, after the Figure 3 position of theparts is attained, moves the link and pawl as a unit, that is, withoutfurther rotation of the pawl relatively to the link, until just beforethe type bar reaches the platen whereupon the link will have becomedisconnected or deflected away from the snatch roll by havingencountered a knock-off 29.

The pawl 22 is thicker than the draw link I!) and is slotted below itstoothed part 30 so that its consequently formed sides which include thetail 24 straddle said draw link. The slotting of the pawl 22 also formsthe stopping corner 21 thereof. The link I9 may be relieved at 3| toclear the top of the pawl slot when the pawl is in the normal Figure 1position relatively to the link I9. Said link l9 may have a returnspring 32 anchored to the framework and cooperating to return the partsto normal position after the link l9 becomes disconnected from thesnatch roll by encountering the knock-off 29.

The period during which the pawl acts as a lever to govern the speed ofthe draw link I9 relatively to the snatch roll may be varied byadjusting the abutment bar 25. To this end said abutment bar may haveelongated slots 31 at its ends which permit rearward or forwardadjustment of said bar relatively to the pawl 22. Fastening screws 36for said bar 25 pass through said slots and are threaded into theframework 35 of the machine.

The bar 25 may be so adjusted that during the lever action of the pawlupon thedraw link [9 the type bar ll moves from its normal Figure 1position to, say, the dotted line position, Figure 1. Such lever actionof the pawl in moving the type bar to said dotted line positionmateriallyreduces the jar and wear which would otherwise attendinitiation of the snatch-roll driven movement of the type action orother snatch roll driven part.

Variations may be resorted to within the scope of the invention, andportions of the improvements may be used without others,

What is claimed is:

1. In a typing machine; the combination with an operatable part, and arotary toothed-snatchroll, of a connector connected tosaid part, atoothed pawl pivoted on said connector, said connector being movableinto position for meshing said pawl with said snatch roll, said pawlbeing initially rotatable to a stop position relatively to saidconnector by said snatch roll upon meshing with the latter, and meansagainst which said pawl reacts during its rotation relative to saidconnector so as to cause said pawl to act as a lever upon said connectorto move said connector initially at a part-operating speed differentfrom the linear speed of the snatch roll teeth.

2. In a typing machine; the combination with an operatable part, and arotary toothed-snatchroll, of a connector connected to said part, a

' toothed pawl pivoted on said connector, said connector being movableinto position for meshing said pawl with said snatch roll, said pawlbeing initially rotatable to a stop position relatively to saidconnector by said snatch roll upon meshing with the latter, meansagainst which said pawl reacts during its rotation relative to saidconnector so as to cause said pawl to act as a lever upon said connectorto move said connector initially at a part-operating speed difierentfrom the linear speed of the snatch roll teeth, and means for adjustingsaid last named means relatively to said pawl for varying the action ofsaid pawl as a lever.

3. In a typing machine having a frame; the combination with anoperatable part and a rotary toothed-snatoh-roll, of a connectorconnected to said part, a toothed pawl pivoted on said connector, saidconnector being movable into position for meshing said pawl with saidsnatch roll, said pawl being initially rotatable to a stop positionrelatively to said connector by said snatch roll upon meshing with thelatter, an abutment on the frame against which said pawl reacts duringits rotation relative to said connector so as to cause said pawl to actas a lever upon said connector to move said connector initially at apart-operating speed less than the linear speed of the snatch rollteeth.

4. In a typing machine having a frame; the

combination with an operatable part and a rotary toothed-snatch-roll, ofa connector connected to said part, a toothed pawl pivoted on saidconnector, said connector being movable into position for meshing saidpawl with said snatch roll, said pawl being initially rotatable to astop position relatively to said connector by said snatch roll uponmeshing with the latter, an abutment on the frame against which saidpawl reacts during its rotation relative to said connector so as tocause said pawl to act as a lever upon said connector to move saidconnector initially at a part-operating speed less than the linear speedof the snatch roll teeth, said abutment being adjustable on said framerelatively to said pawl for varying the action of said pawl as a lever.

5. In a typing machine; the combination with an operatable part, and arotary toothed-snatchroll, of a connector connected to said part, atoothed pawl pivoted on said connector, said connector being movableinto position for meshing said pawl with said snatch roll, said pawlbeing initially rotatable to a stop position relatively to saidconnector by said snatch roll upon meshing with the latter, said pawlhaving a tail, and means against which said tail reacts during rotationof the pawl relatively to said connector so as to cause said pawl to actas a lever upon said connector to move said connector initially at apart-operating speed different from the linear speed of the snatch rollteeth.

6. In a typing machine; the combination of a part movable in a workingstroke, a power-operable mover, a lever, a lever pivot and stop on saidpart, said part being normally positioned so that said lever isdisengaged from said mover, means operable to move said part intoposition to bring an arm of said lever into engagement with said moverso that thereupon said lever is turned by said mover upon said pivotuntil arrested by said stop, and a substantially separate abutmentagainst which another arm of said lever reacts, while turning about saidpivot, to translate the turning of the lever into stroke movement ofsaid part.

7. In a typing machine; the combination of a part movable in a workingstroke, a power-operable mover, a lever, a lever pivot and stop on saidpart, said part being normally positioned so that said lever isdisengaged from said mover, means operable to move said part intoposition to bring an arm of said lever into engagement with said moverso that thereupon said lever is turned by said mover upon said pivotuntil arrested by said stop, and a substantially separate abutmentagainst which another arm of said lever reacts, while turning about saidpivot, to translate the turning of the lever into at least an initialpart of the stroke of said part, said stroke being completed in thatsaid mover moves said part and lever together after said lever isarrested by said stop.

8. In a typing machine; the combination of a part movable in a workingstroke, a rotary snatch-roll, a lever, a lever pivot and stop on saidpart, said part being normally positioned so that said lever isdisengaged fromsaid snatchroll, means operable to move said part tobring an arm of said lever into engagement with said snatch-roll so thatthereupon said lever is turned by said snatch-roll upon said pivot untilarrested by said stop, and a substantially separate abutment againstwhich another arm of said lever reacts, while turning about said pivot,

to translate the turning of the lever into stroke movement of said part.

9. In a typing machine; the combination of a type-actuator movable in atyping stroke, a r0- tary snatch-roll, a lever, a lever pivot and stopon said actuator, said actuator being normally positioned so that saidlever is disengaged from said snatch roll, means operable to move saidactuator into position to bring an arm of said lever into engagementwith said snatch-roll so that thereupon said lever is turned by saidsnatch-roll upon said pivot until arrested by said stop, and asubstantially separate abutment against which another arm of said leverreacts, while turning about said pivot, to translate the turning of thelever into stroke movement of said type-actuator.

10. In a typing machine; the combination of a part movable in a Workingstroke, a rotary snatch-roll, a link connected to said part, a leverpivoted on said link, said link being movable to bring an arm of saidlever into substantially rolling engagement with said snatch roll,whereupon said lever is turned by said snatch roll upon its pivot, saidlever and link having stopmeans to limit the extent of turning of saidlever by the snatch roll, and a substantially separate abutment againstwhich another arm of said lever reacts, while turning about said pivot,to translate the turning of the lever into movement of said link toeffect stroke movement of said part.

HENRY L. PITMAN.

